Actuator for a drainage device



Feb. 27, 1968 V R F. SMITH 3,370,605

ACTUATOR FOR A DRAINAGE DEVICE Filed Nov. 26, 1965 2 Sheets-Sheet 1 lA/VENTOR. R/CHARD E SM/ 7' H Feb. 27, 1968 v R. F. SMITH I 3,370,605

ACTUATOR FOR A DRAINAGE DEVICE Filed Nov. 26, 1965 2 Sheets-Sheet 2 //VVEN7'0R RICHARD FT SM/T H United States Patent )fitice 3,37%,65 Patented Feb. 27, 1968 3,370,605 ACTUATOR FOR A DRAINAGE DEVICE Richard F. Smith, 351 Norwood SE, Grand Rapids, Mich. 49596 Filed Nov. 25, 1965, Ser. No. 599,783 Claims. (Cl. 137187) This invention provides an actuator for a valve mechanism, and produces an automatic operation of the valve according to the presence or absence of a particular liquid in an accumulation chamber. The preferred form of the invention has been developed to remove accumulations of condensate from tanks of compressed air, the condensate being primarily water. The invention has a variety of other applications, but the present discussion will be limited to this preferred form.

The removal of condensate from a tank has usually been accomplished either by manual operation of valves according to visual inspection of the condition of the tank, or by float-operated devices. These latter have normally re quired too much space to be practical, and contain too many Working mechanical parts to be reliable over long periods. Attempts have been made to actuate a drain valve by means of expansion of a member which absorbs Water, but the problem here has been to restore the valve to the original closed condition after the drainage has been completed. The absorptive material does not tend to rid itself of the moisture which is picked up in order to actuate the valve in the first place.

The present invention operates on an entirely different physical principle from absorption. Applicant has discovered that there are certain materials which exhibit a peculiarity with respect to Water, and that this characteristic can be utilized as an actuator for a valve mechanism responsive to the presence or absence of accumulated water. The material most suitable for this actuator has been a series of stacked plates of a plastic material commonly referred to by the trademark Teflon, which is technically designated at tetra-fluor-ethylene. The presence of water around a stack of these plates will tend to cause the water to be present between the plates. The effect between the plates and the water will produce a separation of the plates, and a corresponding increase in the height or length of the stack. Whether this is a surface tension phenomenon, or is due to some other factor, is not clear at this time. The extension of the stack opens a valve, and discharge of the Water removes the extending tendency of the stack permitting the valve to close again. Preferably, the device is biased lightly to a shortened height of the stack by spring forces, or by the action of gravity against a vertically-oriented valve spindle.

The several features of the invention will be analyzed in further detail through a discussion of the particular embodiments illustrated in the accompanying drawing. In the drawing:

FIGURE 1 is an axial section of the complete assembly of the preferred form of the invention, with the valve in the closed position.

FIGURE 2 is a perspective view of the support abutment member.

FIGURE 3 is an axial section of the device shown in FIGURE 1, with the valve in the open position and the stack extended.

FIGURE 4 is an axial section of a modified form of the invention, utilizing a gravity biasing in place of a spring action.

Referring first to FIGURES 1, 2 and 3, the drain device illustrated in the figures includes an accumulation chamber 10 having a top 11 attached with the coupling ring 12. The short section of pipe 13 is for connection to a compressed air tank (not shown), and is preferably welded to the top 11. A hat-shaped screen element 14 has an annular flange interposed between the bottom end of the pipe 13 and the guide 15, which has a bore 16 slidably receiving the top portion 17 of the valve member 18. The lower extremity of the valve member 18 terminates in the needle 19, and the point 20 of this valve needle engages the valve seat 21 of the member 22. The member 22 has a guide portion 23 receiving the needle 19 with clearance so that liquid may move between the needle and the surrounding guide 23 downwardly through the discharge port generally indicated at 24 to a suitable drain connection (not shown). The fitting 25 engages the chamber 10, and also receives the member 22, thus maintaining the concentricity of the valve mechanism. The fitting 25 also receives the locating cup 26 which positions the lower extremity of the shield tube 27. This tube has openings as shown at 28 and 29 for permitting flow of water from the chamber out through the valve.

The principal function of the shield 27 is to maintain the concentricity of the stack of Teflon plates 30. This stack of disks, or plates, is supported on the abutment beam 31 having its opposite ends 32 and 33 resting on the shoulder 34 machined in the inside wall of the chamber 10. Preferably, the support member 31 is provided with opposite flanges 35 for stiffness, and to provide clearance areas for the equalization of the position of the water within the chamber 10. This water flows in from the pipe 13 via the openings 36 and 37 in the guide member 15, and ultimately occupies part of the space surrounding the stack of plates 30.

The upper extremity of the shield tube 27 preferably extends above the stack of plates 30, when there is no substantial amount of water surrounding the stack. This permits the upper plates to still be positioned by the shield tube 27 when the height of the stack has been extended by the presence of water within the chamber 10.

The modification shown in FIGURES 1 and 3 utilizes a spring 38 acting between the cover 11 and the concave washer 39. This washer is preferably of hardened spring steel, and the central diameter is selected to grip the portion 17 of the valve member 18 so that a downward force can be applied to the stack 30, and at the same time cause the valve member 18 to move with the movements of the top of the stack.

Referring to FIGURE 4, a modified form of the invention is shown which eliminates the need for a spring 38 and the washer 39. The valve member 4% has an upper portion 41 slidably received within a guide member 42 in the manner described in connection with FIGURES 1 and 3. The valve member also has a flange 43, which extends out beyond the shield tube 44 to engage the stack of plates directly. Preferably, the flange 43 has an annular recess 45 which permits the extension of the shield tube 44 up beyond the top of the stack 30 so that expansion of the stack under the presence of water can take place with the upper plates remaining in engagement with the shield tube. The weight of the total valve member 40, in the vertically oriented position shown in FIGURE 4, will replace the need for a spring biasing action urging the valve to the closed position shown in FIGURE 4. The stack 30 and the components of the accumulation chamber of FIGURE 4 may be considered as identical to that of FIGURES 1 and 3. With appropriate proportioning of the parts, the guide member 42 may be identical to the guide member 15.

In determining the strength of the spring or the weight of the valve member, the resulting force should be no more than needed to assure closing of the valve on evacuation of the water. The Teflon plates will normally have minute irregularities which will permit water to find its way between them. An excess of spring or weight force will tend to prevent water access by squeezing the plates too tightly together. The closing force should, of course, be less than the opening force generated by the plates. Where the plates are close to absolute flatness, it may be necessary to introduce permeable spacing elements between vthe plates to assure water access.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is my intent to claim the entire invention disclosed herein, except as I am limited by the prior art.

I claim:

1. In combination with a liquid-accumulation chamber and a drain valve for said chamber, said drain valve including a seat member and a valve member, an actuator for said drain valve comprising:

a support abutment fixed with respect to said seat member;

a plurality of detector members each having the characteristics of repulsion for a particular liquid, said detector members being supported on said abutment; and

means adapted to communicate relative movement between said detector members to actuate said valve member whereby the presence of Water in said chamber will cause the opening of said drain valve.

2. An actuator as defined in claiinl, wherein said liquid is water, and said detector members have adjacent surfaces thereof, respectively, of a material identified by the trademark Teflon.

3. An actuator as defined in claim 1, wherein said liquid is water, and said detector members have the adjacent surfaces thereof, respectively, of tetra-fiuor-ethylene.

4. An actuator as defined in claim 1, wherein said detector members are a stacked series of plates.

5. An actuator as defined in claim 4, wherein said stacked plates have a central aperture traversed by an extension of said valve member, said valve member having a flange engaging the opposite extremity of said stacked series of plates from said support abutment.

6. An actuator as defined in claim 5, wherein said valve member has vertical movement between open and closed positions.

7. An actuator as defined in claim 5, additionally including biasing means urging said valveto closed position, said biasing means providing relatively lighter force than the separating force generated by the presence of water at least partially submerging said stacked plates.

3. In combination with a valve mechanism, an actuator comprising:

a plurality of detector members having the characteristic of repelling a particular liquid; said detector, and members constructed and arranged to have relative movement in the presence of said liquid.

means for communicating relative movement between said members to actuate said valve mechanism.

9. An actuator as defined in claim 8, wherein said liquid is water, and said detector members have adjacent surfaces thereof, respectively, of a material identified by the trademark Teflon.

10. An actuator as defined in claim '8, wherein said liquid is water, and said detector members have the adjacent surfaces thereof, respectively, of tetra-fluorethylene.

References Cited UNITED STATES PATENTS 2,564,873 8/1951 Wright 137187 2,845,080 7/1958 Kraft 137199 X 3,120,239 2/1964 Norton 137204 WILLIAM F. ODEA, Primary Examiner.

D. R. MATTHEWS, Assistant Examiner. 

8. IN COMBINATION WITH A VALVE MECHANISM, AN ACTUATOR COMPRISING: A PLURALITY OF DETECTOR MEMBERS HAVING THE CHARACTERISTIC OF REPELLING A PARTICULAR LIQUID; SAID DETECTOR, AND MEMBERS CONSTRUCTED AND ARRANGED TO HAVE RELATIVE MOVEMENT IN THE PRESENCE OF SAID LIQUID, 